1. Field of the Invention
The present invention relates to a tire vulcanizing method using a tire vulcanizer.
2. Description of the Related Art
A tire vulcanizing process is accomplished as follows: First, a tire is inserted into a tire mold, and then the tire mold is closed while forming. After that, a heating/pressurizing medium is introduced into the tire to vulcanize the tire. Next, the tire mold is mounted on a vulcanizer having a mold opening/closing mechanism. After heating and pressurization are performed for a given time, the tire mold is opened to take out the vulcanized tire.
The aforementioned tire mold opening/closing system includes two systems: a system in which a vertical movement and a horizontal movement are combined (usually called a mechanical crank press) and a system using a vertical action only (usually called a hydraulic press). In general, both of the two systems use two sets of molds for the reasons of productivity and ease of use.
When various types of tires are produced, there is a demand that the producer desires to produce tires requiring different vulcanization times by a set of vulcanizer at the same time. Some of the vertically acting systems which meet this demand have been used practically, but the system in which a vertical movement and a horizontal movement are combined (mechanical crank presses), which meets this command, has not been used practically at present.
The reason for this is that on the mechanical crank press, two sets of molds are used by installing to a set of movable beam, so that the times when the molds of both sets are opened are equal. Therefore, two types of tires requiring different vulcanization times cannot be produced at the same time.
Also, the aforementioned vertically acting system has a complicated configuration because it has mold opening/closing devices individually.
The present invention was made to solve the above problem. Accordingly, an object of the present invention is to provide a tire vulcanizing method using a tire vulcanizer, which can vulcanize plural kinds of tires requiring different vulcanization times by using a conventional mechanical crank press or a hydraulic vulcanizing press.